Publications

Ocean Bottom Cable (OBC) seismic data is the preferred method of overcoming subsurface complexity in Bintuni Bay. Its higher fold and wider azimuth coverage has been effective in improving reservoir images below karstified limestone - the major challenge in the Bintuni-Berau Bay area. The capability of dual component OBC data to suppress receiver-side ghost and reverberations is a proven product of combining two different sensors, geophone and hydrophone. Considering the high cost of acquiring OBC seismic, a processing strategy must be carefully chosen to maximize imaging quality of the data. PZ summation, the seemingly simple process of combining the geophone and hydrophone traces, is a critical stage in OBC seismic data processing. Successful application results in enhancing primary reflectors and attenuating reverberations. PZ summation can be approached either in pre-stack or post-stack domain. In this paper, we show an example of OBC PZ summations from the Vorwata field in Bintuni Bay, Papua. In this example, results of pre-stack and post-stack PZ summation are compared. Several PZ summation techniques have been applied to the Vorwata OBC seismic data. A simple but effective summation technique has been chosen for final application based on its significant overall positive impact on the data. The basis of this technique is to perform a Hodogram analysis after phase matching and amplitude adjustment between geophone and hydrophone sensor responses. Hodogram analysis captures the different characteristic of primary and reverberations from geophone and hydrophone. This PZ summationtechnique is effective for multiple attenuation, whether applied pre-stack or post-stack.